The starting point
The EU budget is not a national-style treasury. It is comparatively small, cannot normally run a deficit, and is financed through own resources and other revenue under rules that require extensive agreement between member states.
A federal budget would not need to replace national budgets. It would finance public goods whose scale is genuinely European: shared defence procurement, cross-border energy and rail, frontier research, climate resilience, common digital infrastructure, civil protection, and support when a major shock overwhelms one country.
How this works in practice
Revenue should match the level of the problem. Options debated in Europe include carbon-border revenue, parts of corporate or digital taxation, emissions-related revenue, customs duties, and other shared bases. The exact mix is political; the democratic principle is clearer: European revenue should be legislated openly and scrutinised by the European Parliament.
Federal taxation should not mean that every tax becomes European. Income tax, property tax, local services, and many national choices can remain where voters already understand them. The federal level should raise only what is necessary for its constitutionally defined responsibilities.
What this means for a shared Europe
Borrowing also needs rules. Joint debt can fund exceptional investment or respond to continent-wide crises, but it requires parliamentary control, transparent repayment, independent auditing, and limits that voters can see.
The budget is where federal promises become measurable. If Europe claims responsibility for security, climate, infrastructure, or technological capacity, it should identify the money, the vote, the oversight, and the result.